package com.itheima.reggie.filter;

/**
 * @Author: King-lby
 * @Date Created in 2022-10-29 15:46
 */

import com.alibaba.fastjson.JSON;
import com.itheima.reggie.common.BaseContext;
import com.itheima.reggie.common.R;
import lombok.extern.slf4j.Slf4j;
import org.springframework.util.AntPathMatcher;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

/**
 * 检查用户是否完成登录过滤器
 */
@WebFilter(filterName = "loginCheckFilter",urlPatterns = "/*")
@Slf4j
public class LoginCheckFilter implements Filter {
    //路径匹配器，支持通配符
    public static final AntPathMatcher PATH_MATCHER = new AntPathMatcher();


    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        //清渣UN，向下转型
        HttpServletRequest request = (HttpServletRequest) servletRequest;
        HttpServletResponse response = (HttpServletResponse) servletResponse;
        //1、获取本次请求的URI
        String requestURI = request.getRequestURI();

        log.info("拦截到请求：{}",requestURI);

        //不需要处理的请求路径，定义可以放行的url,选择*放行*
        String[] urls = new String[]{
                "/employee/login",
                "/employee/logout",
                "/backend/**",//静态资源（页面）可以放行，让看不到动态数据即可
                "/front/**",
                "/common/**",
                "/user/sendMsg",//移动端发送短信
                "/user/login",//移动端登录
        };

        //2、判断本次请求是否需要处理
        boolean check = check(urls, requestURI);

        //3、如果不需要处理，则直接放行
        if (check){
            log.info("本次请求{}不需要处理", requestURI);

            filterChain.doFilter(request,response);
            return;
        }

        //4-1、判断登录状态，如果已登录，则直接放行
        if(request.getSession().getAttribute("employee")!= null){
            log.info("用户己登录，用户id为:{})" , request.getSession().getAttribute("employee"));

            //设置当前线程的用户id
            Long empId = (Long) request.getSession().getAttribute("employee");
            BaseContext.setCurrentId(empId);

//            long id = Thread.currentThread().getId();
            filterChain.doFilter(request,response);
            return;
        }
        //4-2、判断移动端用户登录状态，如果已登录，则直接放行
        if(request.getSession().getAttribute("user")!= null){
            log.info("用户己登录，用户id为:{})" , request.getSession().getAttribute("user"));

            //设置当前线程的用户id
            Long userId = (Long) request.getSession().getAttribute("user");
            BaseContext.setCurrentId(userId);

//            long id = Thread.currentThread().getId();
            filterChain.doFilter(request,response);
            return;
        }

        log.info("用户未登录");
        //5、如果未登录则返回未登录结果,通过输出流方式向客户端页面相应数据
        //因为在前端中有一个“request.js",其中有一个响应拦截器，可以通过判断返回登录页面
        response.getWriter().write(JSON.toJSONString(R.error("NOTLOGIN")));
        return;
    }

    /**
     * 路径匹配，检查本次请求是否需要放行
     * @param urls
     * @param requestURI
     * @return
     */
    public boolean check(String[] urls,String requestURI){
        for (String url : urls) {
            boolean match = PATH_MATCHER.match(url, requestURI);
            if (match){
                return true;
            }
        }
        return  false;
    }
}
